The following is confirmation received regarding expectations for updates to OPRA Options data. This information has been verified from the feed we receive for OPRA.
Only VIX and SPX index options trade early (between 3 am and 9:15 ET). All equity options start quoting at 9:30 am ET.
Any quotes seen prior to 9:00 am ET are the final quotes of the *prior day*. Between 9 am and 9:30am, it is expected to generally see no quotes at all. This is because OPRA sends an event around 9am that clears any stale quotes.
We used to clear the final quotes of the *prior day* earlier in the morning but we received complaints from Clients who wanted the prior day quote to persist and not be cleared so early. Unfortunately, because of this, there is no exact or best time to do a cut-off so we simply clear the prior day data based on what is sent to us in the feed.